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Related papers: Magnetic Accretion Onto White Dwarfs

200 papers

We have used a model of magnetic accretion to investigate the rotational equilibria of magnetic cataclysmic variables (mCVs). The results of our numerical simulations demonstrate that there is a range of parameter space in the P_spin /…

Astrophysics · Physics 2009-11-10 A. J. Norton , G. A. Wynn , R. V. Somerscales

Our recent theoretical work (Townsley and Bildsten 2002) on the thermal state of white dwarfs (WDs) in low mass transfer rate binaries allows us to predict the broadband colors of the binary from those of the WD and companion when the disk…

Astrophysics · Physics 2007-05-23 Dean M. Townsley , Lars Bildsten

The magnetic fields of the accreting white dwarfs (WDs) in magnetic cataclysmic variables (mCVs) determine the accretion geometries, the emission properties, and the secular evolution of these objects. We determine the structure of the…

Astrophysics · Physics 2015-06-24 K. Beuermann , F. Euchner , K. Reinsch , S. Jordan , B. T. Gaensicke

The increasing number of synoptic surveys made by small robotic telescopes, such as the photometric Catalina Real-Time Transient Survey (CRTS), represents a unique opportunity for the discovery of variable sources and improves the…

In cataclysmic variables (CVs), accretion onto white dwarfs produces high temperature, high density plasmas. They cool down from kT~10 keV via bremsstrahlung continuum and K and L shell line emissions. The small volume around white dwarfs…

Astrophysics · Physics 2007-05-23 Koji Mukai

The white dwarf in AM Her systems is strongly magnetic and keeps in synchronous rotation with the orbit by magnetic coupling to the secondary star. As the latter evolves through mass loss to a cool, degenerate brown dwarf it can no longer…

Astrophysics · Physics 2009-10-31 F. Meyer , E. Meyer-Hofmeister

Although the theory of cataclysmic variable (CV) evolution is able to explain several observational aspects, strong discrepancies have existed for decades between observations and theoretical predictions of the orbital period distribution,…

Solar and Stellar Astrophysics · Physics 2019-09-30 Monica Zorotovic , Matthias R. Schreiber

Magnetic cataclysmic variables are close binary systems containing a strongly magnetized white dwarf that accretes matter coming from an M-dwarf companion. High-energy radiation coming from those objects is emitted from the accretion column…

High Energy Astrophysical Phenomena · Physics 2015-06-24 C. Busschaert , E. Falize , C. Michaut , J. -M. Bonnet-Bidaud , M. Mouchet

In this paper we review the current status of research on the observational and theoretical characteristics of isolated and binary magnetic white dwarfs (MWDs). Magnetic fields of isolated MWDs are observed to lie in the range 10^3-10^9G.…

Solar and Stellar Astrophysics · Physics 2015-06-03 Lilia Ferrario , Domitilla de Martino , Boris Gaensicke

The accretion column in magnetic Cataclysmic Variables may have a not negligible Thomson optical depth. A fraction of the thermal radiation from the post-shock region may therefore be scattered - and then polarized - before escaping the…

Astrophysics · Physics 2009-11-10 Giorgio Matt

Accreting white dwarfs (WDs) constitute a significant fraction of the hard X-ray sources detected by the INTEGRAL observatory. Most of them are magnetic Cataclysmic Variables (CVs) of the intermediate polar (IP) and polar types, but the…

The processes of accretion of the gaseous blobs with different masses and densities onto strongly magnetized white dwarfs in the systems of polars have been modeled. We have proved that shot noise in blue wavelengths represents accretion of…

Astrophysics · Physics 2007-05-23 A. V. Halevin , I. L. Andronov , N. M. Shakhovskoy , S. V. Kolesnikov , N. I. Ostrova

We present constraints on the space densities of both non-magnetic and magnetic cataclysmic variables, and discuss some implications for models of the evolution of CVs. The high predicted non-magnetic CV space density is only consistent…

Solar and Stellar Astrophysics · Physics 2014-07-14 Magaretha L. Pretorius

We present the first population synthesis of synchronous magnetic cataclysmic variables, called polars, taking into account the effect of the white dwarf (WD) magnetic field on angular momentum loss. We implemented the reduced magnetic…

Solar and Stellar Astrophysics · Physics 2019-12-25 Diogo Belloni , Matthias R. Schreiber , Anna F. Pala , Boris T. Gänsicke , Mónica Zorotovic , Claudia V. Rodrigues

We discuss the evolution of the magnetic field of an accreting white dwarf. We first show that the timescale for ohmic decay in the liquid interior is 8 to 12 billion years for a dipole field, and 4 to 6 billion years for a quadrupole…

Astrophysics · Physics 2009-11-07 Andrew Cumming

Magnetic cataclysmic variables (CVs) contain a white dwarf with magnetic field strong enough to control the accretion flow from a late type secondary. In this paper, we discover a magnetic CV (CXOGSG J215544.4+380116) from the $Chandra$…

Solar and Stellar Astrophysics · Physics 2017-02-01 Song Wang , Yu Bai , Chuan-peng Zhang , Ji-feng Liu

Accreting white dwarfs in Cataclysmic variables (CVs) show short-period (tens of minutes) brightness variations that are consistent with non-radial oscillations similar to gravity (g) modes observed in isolated white dwarfs (WDs). GW…

Solar and Stellar Astrophysics · Physics 2023-07-19 Praphull Kumar , Dean M. Townsley

In this review talk I cover some recent developments in understanding the role that magnetic fields play in cataclysmic variables. I discuss the recent DNO--QPO unification models; the disk--magnetosphere boundary; some issues concerning…

Astrophysics · Physics 2007-05-23 Coel Hellier

AM Her variables -- synchronised magnetic cataclysmic variables (CVs) -- exhibit a different period distribution from other CVs across the period gap. We show that non-AM Her systems may infiltrate the longer-period end of the period gap if…

Astrophysics · Physics 2009-11-07 R. F. Webbink , D. T. Wickramasinghe

We have started a systematic study of the field topologies of magnetic single and accreting white dwarfs using Zeeman tomography. Here we report on our analysis of phase-resolved flux and circular polarization spectra of the magnetic…

Astrophysics · Physics 2007-05-23 K. Reinsch , F. Euchner , K. Beuermann , S. Jordan , B. T. Gaensicke